1. Field
The present disclosure relates to cell capturing filters having a high aspect ratio, and more particularly, to cell capturing filters capable of easily capturing cells or particles of a predetermined size or greater in a sample, preventing clogging of a flow passage by the captured cells or particles, and reducing stress applied to the captured cells or particles.
2. Description of the Related Art
Early detection is of vital importance for treating various forms of cancer, and much research is being conducted to find cancer detection methods that are fast, simple, and accurate. Recently, a cancer diagnosis method performed by capturing a circulating tumor cell (CTC) from a blood sample has been suggested. However, it is difficult to capture CTCs due to low concentrations of CTCs in blood, e.g., only one CTC may be found among 109 cells. For instance, with regard to breast cancer, about five or less CTCs may be found in about 7.5 ml of blood, and with regard to large intestine cancer, about three or less CTCs may be found in about 7.5 ml of blood. Thus, for an accurate diagnosis of cancer, the rare CTCs need to be captured without loss. Moreover, CTCs die easily, and thus, capturing needs to be conducted while minimizing adverse conditions to the cells.
Capturing CTCs may be conducted by using a filter that allows erythrocytes and leucocytes in blood to pass through and filters only CTCs. However, this type of filter usually has a structure in which multiple, column-shaped, and complicated patterns are formed in minute flow passages through which blood may flow. While erythrocytes and leucocytes, which have a relatively small size, may pass through these patterns, CTCs which are relatively large may be captured between the patterns. However, the flow passages may be clogged by the captured CTCs. Once clogging occurs, stress is applied to the CTCs and the CTCs may be damaged, and leucocytes may be captured together with the CTCs, which decreases the analysis efficiency and increases the analysis time.